Electrolyte additive, obtained electrolyte and lithium ion battery

The invention provides an electrolyte additive, an obtained electrolyte and a lithium ion battery, and belongs to the technical field of lithium ion battery electrolytes. The electrolyte additive provided by the invention can accelerate the formation of compact membranes on the surfaces of positive and negative electrode materials, prevent transition metal dissolution of the positive electrode material, stabilize the positive electrode, improve the energy density of the lithium ion battery, and effectively improve the cycle performance, safety performance and stability of the lithium ion battery at high temperature and high pressure. 本发明提供了一种电解液添加剂及所得电解液、锂离子电池，属于锂离子电池电解液技术领域。本发明提供的电解液添加剂能够加速正极和负极材料表面致密膜的形成，防止正极材料发生过渡金属溶出，并稳定正极，提高锂离子电池的能量密度，可有效提升锂离子电池在高温高压下的循环性能、安全性能和稳定性。